Bouncing to non-existing domain

I get these warnings by fetchmail: reading message 1 of 2 (3113 octets) .fetchmail: SMTP error: 553 5.1.8 ... Domain of sender address jimc@xena.cft.ca.us does not exist fetchmail: mail from FETCHMAIL-DAEMON@kleigh.nl bounced to jimc@xena.cft.ca.us What is the point of bouncing a message to a domain you know does not exist? These warnings always result in two error-messages in my inbox about mail that could not be delivered. Undoubtedly some security feature, but is there a way to switch it of? It is quite annoying. I'm using SuSE 8.0. -- Peter Kleiweg http://www.let.rug.nl/~kleiweg/